Spring assembly and method of manufacture

ABSTRACT

A spring assembly includes a top mesh comprising two transverse groups of wires and a border frame, which are welded together at points of intersection. The assembly also includes a number of compression springs, either coils, saddle-shaped springs, or other types. One of the groups of wires is formed with a series of bights located between the intersections of the wires, and these wires are arranged in adjacent pairs whose bights extend in opposite directions. Each of the springs has two upper portions for attachment to the mesh, and these are spaced apart a different distance than the adjacent wires, but substantially the same as the distance between the bights of adjacent wires. The springs are assembled by deflecting them or the adjacent mesh wires enough to permit the attachment portions of the springs to pass between the bights and abut against the mesh wires. The bights are then allowed to return to their original form, in which they engage the spring attachment portions to secure them in place on the mesh.

United States Patent [191 Ciampa et al.

[ SPRING ASSEMBLY AND METHOD OF MANUFACTURE [75] Inventors: Fred A. Ciampa; Angelo Serafini;

both of East Boston; Louis Mazzarella, Boston, all of Mass.

[73] Assignee: Standard Box Spring Company, East Boston, Mass.

221 Filed: Aug. 6, 1971 211 App]. No.: 169,724

[52] US. Cl. 267/101, 267/108 [51] Int. Cl F16! 3/02 [58] Field of Search 267/101, 107, 108

[56] References Cited UNITED STATES PATENTS 3,049,377 8/1962 Asaro et al. 267/107 FOREIGN PATENTS OR APPLICATIONS 708,781 5/1954 Great Britain 267/101 Aug. 28, 1973 Primary Exqminer.lames Marbe rt V Attorney- David A. Rich, William L. Ericson et a1.

[57] ABSTRACT A spring assembly includes a top mesh comprising two transverse groups of wires and a border frame, which are welded together at points of intersection. The assembly also includes a number of compression springs, either coils, saddle-shaped springs, or other types. One of the groups of wires is formed with a series of bights located between the intersections of the wires, and these wires are arranged in adjacent pairs whose bights extend in opposite directions. Each of the springs has two upper portions for attachment to the mesh, and these are spaced apart a different distance than the adjacent wires, but substantially the same as the distance between the bights of adjacent wires. The springs are assembled by deflecting them or the adjacent mesh wires enough to permit the attachment portions of the springs to pass between the bights and abut against the mesh wires. The bights are then allowed to return to their original form, in which they engage the spring attachment portions to secure them in place on the mesh.

10 Claims, 10 Drawing Figures Patented Aug. 28,1973 I 3,754,744

WWI.

Patented Aug. 28, 1973 2 Sheets-Sheet 2 A i sz QEN SPRING ASSEMBLY AND METHOD OF MANUFACTURE BACKGROUND AND BRIEF DESCRIPTION OF THE INVENTION The present invention concerns improvements in means for attaching compression springs to the top surface portion of a box spring or other furniture spring assembly.

Our US. Pat. No. 3,270,354, issued Sept. 6, 1966, pertains to a Furniture Spring Assembly in which a top mesh is formed by welding two groups of intersecting wires to one another and securing this mesh to a border frame. Coil springs have opposite sides of their top turns tangential to adjacent pairs of mesh wires, and are attached by locking means which releasably connect them to the mesh. These locking means may take the form of locking wires, clips, or the like. While that method of assembly is satisfactory, it does require the provision and attachment of locking means separate from the coils and the mesh. One method of eliminating this requirement is disclosed and claimed by our US. Pat. No. 3,577,574, issued May 4, 1971 for Spring Assembly For Furniture And Method Of Manufacture. According to that patent, one group of the mesh wires is formed with open channels arranged in opposed pairs and spaced to receive diametrallyopposed parts of the top turn of a coil spring. The mesh acts as ajig which automatically positions the coils. The assembly is completed by upsetting the return bends that form the channels. In connection with furniture spring assemblies of the kind that incorporate saddleshaped springs, our US. Pat. No. 3,546,723, issued Dec. 15, 1970 for a Box Spring shows the attachment of the saddle springs to a wire mesh by means of separate clips. A method for overcoming the need for separate clips is disclosed and claimed in our copending US. Patent application Ser. No. 97,727, filed Dec. 14, 1970 for Box Spring And Method Of Assembly, and involves the formation of upsettable channels in the mesh wires.

It is the principal object of the present invention to provide an improved furniture spring assembly in which compression springs are attached to a wire mesh without the use of separate fastening means. It is a further object to provide an improved method for assembling compression springs with a wire mesh to form a furniture spring. Other objects and advantages of the invention will appear as the following description proceeds.

Briefly stated, according to a preferred embodiment and mode of practice of our invention, atop mesh is first formed of two groups of wires, one of which is formed with longitudinally-spaced bights which extend transverse to the length of each wire in a common direction. The two groups of wires are laid in transverse relation, one on top of the other, with their points of mutual intersection spaced alternately between the bights. A rectangular border frame is laid around the crossed wires to engage the ends of both groups, and the resulting mesh is welded at all points of intersection. The wires having bights are arranged in adjacent pairs, which have their bights extending generally parallel to the plane of the mesh, and in opposite directions. Compression springs of'the coil, saddle, or other type suitable for the intended use of the assembly, each afford two portions for attachment to the mesh. These portions are spaced apart at distances slightly different from the spacing between each adjacent pair of the wires having bights, but at substantially the same distance as that between oppposed bights in each adjacent pair of wires. The springs are assembled to the mesh by deflecting either the springs, or the wires of adjacent pairs in the regions of their bights, or both, enough so that the attachment portions of the springs can pass between the bights. The parts must be so proportioned that the necessary deflection does not exceed the elastic limit of deformation of the wires or springs. If the mesh wires are to be deflected, one must take into consideration the length of free wire between their welded points of intersection, which cannot be deflected. The attachment portions of the springs are then brought to bear against the mesh wires. Thereafter, the deflected springs or bight regions of the wires are released, and return elastically to their original configuration and spacing, so that they engage the attachment portions of the springs on surfaces opposite to the mesh. The springs are thus held firmly to the mesh by the bights.

In an alternative construction specifically involving saddle-shaped springs, the bights may be formed in the top legs of the saddle springs, rather than in the mesh wires. Because the saddle spring wires should generally be of agreater gage and stiffness than the mesh wires,

it is preferred to form return bends in the mesh wires, projecting out of the plane of the top mesh in positions to engage the bights, so as not to unduly distort the mesh from a planar configuration when the springs are assembled. In this construction, the spacing between opposed bights in the two top legs of each saddle spring is such that the bights would interfere with assembly with the mesh in the undeformed condition of the spring. The saddle springs or the mesh wires are deflected, and the top legs of the saddle spring are then engaged between the bights and the mesh, and so held in assembled relation.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a fragmentary view in perspective of a first embodiment of our improved furniture spring assembly, incorporating saddle springs,

FIG. 2 is a fragmentary plan view showing part of a complete spring assembly, in which the portion nearest the top of the paper shows only the upper parts of the. assembly, and the lower portion shows only the bottom parts, for the sake of increased clarity;

FIG. 3 is a fragmentary cross-sectional view in side elevation, illustrating the method of attachment of the springs to the mesh in the assembly of FIGS. 1 and 2;

FIG. 4 is a fragmentary cross-sectional view similar to FIG. 3, but showing the springs after attachment to the mesh;

FIG. 5 is a fragmentary plan view ofa modified spring assembly incorporating saddle springs;

FIG.-6 is a fragmentary cross-sectional view .of the assembly;

FIG. 7 is a-fragmentary bottom plan view of another embodiment of the invention, which employs coil springs;

FIG-8 is a fragmentary view in frontelevation of the assembly in FIG. 7;

FIG. 9 is a fragmentary view in side elevation of the same assembly; and

FIG. 10 is a fragmentary view ofa modified form of bight.

Referring first to FIGS. 1-4, a first form of the im proved spring assembly includes a top mesh comprising a first group of parallel wires 22 extending laterally of the spring assembly, a second group of parallel wires 24 extending longitudinally, and a generally rectangular wire border frame 21. Each of the wires 22 is formed before assembly with a series of spaced bights 20, all of which extend in a common direction transverse to the length of the wire. As shown, the bights are generally Vee-shaped, but they may take various forms.

The border frame 21 is placed on a plane assembly surface. The wires 22 are laid in parallel relation on the surface, and the wires 24 are then laid across them in parallel rows. The border frame 21 is positioned to engage the ends of both groups of wires. The bights 20 rest on and extend parallel to the assembly surface. The bights 20 are so bent that they lie out of the common plane of the wires 22. Pairs of adjacent wires 22 have their bights arranged in opposed relation and extending in opposite directions parallel to the surface on which the wires rest; in the form shown, the bights of adjacent pairs of wires extend toward one another, but they may alternatively extend away from one another.

The wires 22 and 24 are of such lengths that the ends f both groups terminate at the border wire. The mesh is completed by welding all of the intersections 26 between the wires 22 and 24 and the frame 21. The mesh so formed in then inverted on the assembly surface.

The next step in the assembly is the formation of a number of saddle springs and half-saddle springs 11. Each half saddle spring 11 is bent from a single length of wire, to form a pair of parallel bottom legs 13, a pair of parallel upwardly sloping legs 15 connected to the bottom legs by curved portions 14, and a transverse top leg 17 connected to the sloping legs by curved portions 16. The top leg 17 is parallel to the common plane of the bottom legs 13, but extends transverse to these legs. It is convenient and economical to form the full saddle springs 10 by welding together the free ends of the bottom legs 13 of two half-saddle springs, as shown at 12, although the full saddle springs may also be formed from single lengths of wire.

In the full saddle springs 10, thetwo top legs 17 are parallel to one another. In the embodiment shown in FIGS. 14, the top legs 17 are spaced apart at a distance slightly less than the spacing between pairs of adjacent wires 22, but substantially the same distance as the spacing between the opposed bights 20 in these wires. In an alternative construction in which the opposed bights 20 extend away from rather than toward one another, the spacing between the top legs 17 would remain substantially equal to the distance between the opposed bights 20, but would be slightly greater than the distance between the pairs of wires 22. Thus, prior to completion of the assembly, and in an undistorted condition of the mesh and the saddle springs as illustrated in FIG. 3, the bights would interfere with attempts to assemble the mesh with the saddle springs.

The method of assembling the saddle springs with the mesh is illustrated in FIGS. 3 and 4, which show the parts in an upright position for the sake of greater clarity, although assembly is normally done with the mesh in an inverted position on the assembly surface.

To assemble each spring 10 with the top mesh, the top legs 17 are deflected inwardly in the directions shown by the arrows A in FIG. 3, until their spacing is less than that between opposed bights 20 in the wires 22. At the same time, the wires 22 may, if desired, be deflected apart in the regions of the bights to assist in admitting the legs 17; or if the saddle springs are especially stiff, the wires 22 may alone be subjected to deflection. The top legs are then passed between the bights in the directions of the arrows B, and brought to bear against the mesh wires 24. The spring and wires are then released, allowing the top legs to reach the positions shown in FIG. 4, each leg being received within a pair of bights 20 in one wire 22. The top legs 17 comprise attachment portions of the spring, which are engaged against their upper surfaces by the mesh wires 24, and against their opposed bottom surfaces by the bights 20.

The relative spacing between the legs or attachment portions of the springs, the distances between the mesh wires 22, and the depth of the bights 20 must be so selected that the springs and the mesh can be assembled by means of deflections which do not exceed the elastic limits of deformation of the springs or the wires, so that the springs and wires will return to their original undistorted forms when released. If the mesh wires are to be deflected to permit the assembly of the springs, it must be borne in mind that these wires may not be moved at their welded intersections 26; but the lengths of wire containing the bights and falling between these intersections may be deflected sufficiently, provided that the depths of the bights are small enough to allow the attachment portions of the springs to pass them without distorting the wires beyond their limits of elastic deformation.

The half-saddle springs 11 are preferably used at the ends or sides, or both, of the spring assembly as shown in FIG. 2, adjacent to the border wire 21, so that the edges of the completed spring will be firmly supported but will have no protrusions. FIG. 2 shows a simplified arrangement for the sake of clarity, in which the border wire is not directly connected to any of the saddle springs. In this form, half-saddle springs 11 having single upper legs 17 are attached at each end of the assembly by the bights of single wires 22. It may, however, be preferable to attach the half-saddle springs to the mesh or directly to the border wire by means of conventional clips or lock wires, for increased security. The upper portion of FIG. 2 shows only the top parts of the assembled spring, including the border frame, top mesh, and saddle springs.

The final stage of assembly is concerned with the attachment of the bottom legs 13 of the saddle springs 10 and 11 to a wood bottom frame comprising longitudinal beams 38 and transverse slats 36. Each bottom leg 13 is formed with a partial loop 28, so positioned as to rest on one of the slats 36 or beams 38. These loops receive recessed disks 30, as more fully described in our aforementioned US. Pat. No. 3,414,9l5. Each disk has a central hole for receiving a nail 34. The box spring is completed by inverting the assembly of the top mat and the saddle springs to rest on the bottom frame, inserting a disk 30 in each loop 28, and driving a nail 34 through each disk into the slats 36 or beams 38. This step may be carried out either manually or automatically, and completes the spring assembly.

As shown in FIGS. 1 and 2, the loops 28 are circular in form; however, they may have other shapes to simplify bending, which are also adapted to be gripped firmly by the disks 30. The bottom legs of the saddle springs may alternatively be attached to the bottom frame by other means, such as staples, or conventional straps and nails. In that case, the bottom legs of the springs and 11 would be made straight, and do not require the loops 28.

A modification is shown in FIGS. 5 and 6 in which a plurality of opposed bights 52 are formed in the top legs 17! of saddle springs 10, rather than in the mesh wires 22. These bights extend in opposite directions; in the construction shown, they face one another, but they may face apart. Correspondingly, the undistorted spacing between the opposed top legs 17' is slightly more than the spacing between the wires 22 of the mesh; whereas it would be slightly less if the bights faced apart. The spacing between opposed bights 52 of the two top legs is, however, substantially the same as the distance between each pair of wires 22'.

To facilitate assembly, return bends 50 are formed in the top wires 22' at such locations as to receive the bights 52. The assembly method is similar to that of FIGS. 3 and 4, in that the legs 17' are deflected away from one another, while opposed wires 22 may also or alternatively be deflected toward one another, enough so that the saddle springs can be brought into engagement with the top wires 24, passing outside the return bends 50. When the springs and wires are released and allowed to return to their undistorted form, the bights 52 are received over the bends 50. Again, the legs 17 comprise attachment portions of the saddle springs, engaged on one surface by the wires 24 and on an opposite surface by the bends 50 of the wires 22.

FIGS. 7-9 illustrate another embodiment of the improved spring assembly incorporating conventional coil springs 40, in which the uppermost end of each coil is secured by a knot 42. The mesh comprises top wires 22 and 24 and a border frame 21 (not shown), which are the same as in the preceding embodiments. The wires 22 are formed with bights spaced between the welded intersections 26 of the top wires. In the form shown, the bights of each pair of adjacent wires face away from one another, but it should be understood that they might equally well be directed toward one another, provided that the spacing between the wires 22 were made greater instead of less than the diameter of the top coil of the spring 40. In the undistorted condition of the mesh wires, the spacing between opposed pairs of bights 20 is substantially the same as the diameter of the coil. The spring is assembled by pressing the opposed bights 20 toward one another, deflecting the wires 22 in the regions between adjaceht welds 26 sufficiently so that the upper coil of the spring 40 may be brought to bear against the lower surfaces of the wires 24. The bights are then released and allowed to return to their undistorted positions, as shown in FIGS. 7-9. It is preferable not to deflect the coil 40 to assist the assembly procedure, since conventional coils can be deflected only very slightly without becoming permanently deformed. Each coil 40 is securely held in place by the engagement of its upper most turn, which provides two diametrally-opposed attachment portions, between the mesh wires and the bights 20.

The precise configuration of the bights in any of the illustrated embodiments is not critical, and a U-shaped bight 55 is illustrated in a mesh wire 56 in FIG. 10 as one example of various configurations which the bights may assume.

We claim:

1. A spring assembly for furniture comprising a wire mesh formed of a border wire and two groups of wires lying parallel to a common plane, said groups of wires being transverse to one another and having their ends terminating at said border wire, said border wire and said groups of wires being welded together at points of intersection therebetween to restrain said wires against relative movement, the wires of each group being substantially parallel to one another;

the wires of one of said groups being formed with a plurality of spaced bights having extent substantially parallel to said common plane and each located between adjacent points of intersection between said wires, the wires of said one group being arranged in adjcent pairs having their said bights in opposed relation and extending in opposite directions parallel to said common plane;

together with a plurality of compression springs, each of said springs having at least two attachment portions extending in said common plane and spaced apart when undistorted a distance different from the spacing between each of said pairs of said one group of wires but substantially the same as the spacing between opposed ones of said bights thereof, such that said bights interfere, prior to assembly of said springs with said mesh, with placement of said attachment portions into engagement with said mesh; said wires being transversely deflectable within their elastic limits to an extent which permits said attachment portions to be passed over said bights and brought into engagement with said mesh, and said wires being elastically restored following such deflection to their original spacing;

opposed bights in each of said adjacent pairs of wires engaging first surfaces of said attachment portions of a corresponding one of said springs, and said mesh engaging second surfaces of said attachment portions opposite to said first surfaces, whereby said attachment portions of each of said springs are held in assembled relation with said mesh by their engagement between said bights and said mesh.

2. An assembly as recited in claim 1, in which said one group of wires are arranged with said pairs of adjacent wires having said bights thereof facing toward one another, and said compression springs are formed with said attachment portions spaced apart a distance less than the spacing between said pairs of adjacent wires.

3. An assembly as recited in claim 1, in which said one group of wires are arranged with said pairs of adjacent wires having said bights thereof facing away from one another, and said compression springs are formed with said attachment portions spaced apart a distance greater than the spacing between said pairs of adjacent wires.

4. An assembly as recited in claim 1, in which said two attachment portions of each of said compression springs are formed as substantially rectilinear top legs 7 legs, and having upwardly sloping legs connecting said top legs with said bottom legs.

6. An assembly as recited in claim 1, in which each of said compression springs is formed as a helical coil of which a top turn provides said two attachment portions.

7. A spring assembly for furniture comprising a wire mesh formed of a border wire and two groups of rectilinear wire members lying parallel to a common plane, said groups of wires being transverse to one another and having their ends terminating at said border wire, said border wire and said groups of wires being welded together at points of intersection therebetween to form a mesh and to restrain said wires against relative movement, the wires within each group being substantially parallel to one another;

a group of saddle-shaped compression spring members, each of said spring members having two attachment portions comprising substantially rectilinear and parallel attachment leg portions lying parallel to said common plane and being spaced apart when undistorted a predetermined distance;

one of said groups of members being formed each with a plurality of spaced bights arranged in opposed pairs spaced apart a distance to cause interferenced with assembly with said members of one other of said groups when undistorted; said one group of members being transversely deflectable within their elastic limits to an extent which removes said interference, and being elastically restored following such deflection to their original spacing; said oppos'ed pairs of bights extending in opposite directions parallel to said common plane;

each of said pairs of opposed bights engaging a corresponding one of said members of said other of said groups to secure said saddle-shaped spring memhere to said mesh.

8. An assembly as recited in claim 7, in which said oneof said groups comprises a group of said wire members, said one group being arranged with pairs of adjacent wire members having said bights thereof in opposed relation and extending in opposite directions parallel to said common plane, said group of spring members comprising said other of said groups.

9. An assembly as recited in claim 7, in which said one of said groups comprises said group of spring members, each said spring member having opposed bights in said two leg portions thereof, one of said groups of wire members comprising said other of said groups.

10. An assembly as recited in claim 7, in which each of said saddle-shaped compression springs is formed with a pair of bottom legs parallel to one another and extending in a plane parallel to but spaced from said parallel attachment leg portions, and with upwardly sloping legs connecting said bottom legs with said attachment leg portions. 

1. A spring assembly for furniture comprising a wire mesh formed of a border wire and two groups of wires lying parallel to a common plane, said groups of wires being transverse to one another and having their ends terminating at said border wire, said border wire and said groups of wires being welded together at points of intersection therebetween to restrain said wires against relative movement, the wires of each group being substantially parallel to one another; the wires of one of said groups being formed with a plurality of spaced bights having extent substantially parallel to said common plane and each located between adjacent points of intersection between said wires, the wires of said one group being arranged in adjcent pairs having their said bights in opposed relation and extending in opposite directions parallel to said common plane; together with a plurality of compression springs, each of said springs having at least two attachment portions extending in said common plane and spaced apart when undistorted a distance different from the spacing between each of said pairs of said one group of wires but substantially the same as the spacing between opposed ones of said bights thereof, such that said bights interfere, prior to assembly of said springs with said mesh, with placement of said attachment portions into engagement with said mesh; said wires being transversely deflectable within their elastic limits to an extent which permits said attachment portions to be passed over said bights and brought into engagement with said mesh, and said wires being elastically restored following such deflection to their original spacing; opposed bights in each of said adjacent pairs of wires engaging first surfaces of said attachment portions of a corresponding one of said springs, and said mesh engaging second surfaces of said attachment portions opposite to said first surfaces, whereby said attachment portions of each of said springs are held in assembled relation with said mesh by their engagement between said bights and said mesh.
 2. An assembly as recited in claim 1, in which said one group of wires are arranged with said pairs of adjacent wires having said bights thereof facing toward one another, and said compression springs are formed with said attachment portions spaced apart a distance less than the spacing between said pairs of adjacent wires.
 3. An assembly as recited in claim 1, in which said one group of wires are arranged with said pairs of adjacent wires having said bights thereof facing away from one another, and said compression springs are formed with said attachment portions spaced apart a distance greater than the spacing between said pairs of adjacent wires.
 4. An assembly as recited in claim 1, in which said two attachment portions of each of said compression springs are formed as substantially rectilinear top legs extending in parallelism to one another, each said attachment portion being engaged with a plurality of said bights in a corresponding one of said one group of wires.
 5. An assembly as recited in claim 4, in which said compression springs are formed in a saddle shape, having a pair of bottom legs parallel to one another and extending in a plane parallel to but spaced from said top legs, and having upwardly sloping legs connecting said top legs with said bottom legs.
 6. An assembly as recited in claim 1, in which each of said compression springs is formed as a helical coil of which a top turn provides said two attachment portions.
 7. A spring assembly for furniture comprising a wire mesh formed of a border wire and two groups of rectilinear wire members lying parallel to a common plane, said groups of wires being transverse to one another and having their ends terminating at said border wire, said border wire and said groups of wires being welded together at points of intersection therebetween to form a mesh and to restrain said wires against relative movement, the wires within each group being substantially parallel to one another; a group of saddle-shaped compression spring members, each of said spring members having two attachment portions comprising substantially rectilinear and parallel attachment leg portions lying parallel to said common plane and being spaced apart when undistorted a predetermined distance; one of said groups of members being formed each with a plurality of spaced bights arranged in opposed pairs spaced apart a distance to cause interferenced with assembly with said members of one other of said groups when undistorted; said one group of members being transversely deflectable within their elastic limits to an extent which removes said interference, and being elastically restored following such deflection to their original spacing; said opposed pairs of bights extending in opposite directions parallel to said common plane; each of said pairs of opposed bights engaging a corresponding one of said members of said other of said groups to secure said saddle-shaped spring members to said mesh.
 8. An assembly as recited in clAim 7, in which said one of said groups comprises a group of said wire members, said one group being arranged with pairs of adjacent wire members having said bights thereof in opposed relation and extending in opposite directions parallel to said common plane, said group of spring members comprising said other of said groups.
 9. An assembly as recited in claim 7, in which said one of said groups comprises said group of spring members, each said spring member having opposed bights in said two leg portions thereof, one of said groups of wire members comprising said other of said groups.
 10. An assembly as recited in claim 7, in which each of said saddle-shaped compression springs is formed with a pair of bottom legs parallel to one another and extending in a plane parallel to but spaced from said parallel attachment leg portions, and with upwardly sloping legs connecting said bottom legs with said attachment leg portions. 